Many of the victims of what became known as the "Caravan of Death" had voluntarily turned themselves into the military authorities.

Prisoners were taken from their cells and summarily executed, often without the knowledge or consent of the local military authorities.

Analysts say the events set the seal on Chile's long military dictatorship.

The army unit travelled from town to town in a Puma helicopter, armed with grenades, machine guns and knives.

Trail of terror

The Puma landed in Cauquenes, La Serena, Copiapo, Antofagasta, Calama in northern Chile and at least one southern city.

Officially, the delegation's mandate had been to "review the War Council proceedings for political prisoners in the regions and bring procedures there in line with Santiago standards".

Supporters of the campaign to bring General Pinochet to justice for abuses during his 1973-1990 rule say he had clear responsibility for the slaughter, sending a close associate to head the "delegation".

Lawyers for the former ruler say the 85-year-old is in poor health and is unable to mount a proper defence.

He "never ordered any executions much less kidnappings," says Pinochet lawyer Ricardo Rivadeneira.